Various techniques for protecting data against disaster events are known in the art. For example, U.S. Patent Application Publication 2009/0216969, whose disclosure is incorporated herein by reference, describes a method for data protection that uses a disaster-proof storage unit. Data is accepted for storage from one or more data sources. The data is sent for storage in a primary storage device and in a secondary storage device. While awaiting an indication of successful storage of the data in the secondary storage device, a record associated with the data is temporarily stored in a disaster-proof storage unit adjacent to the primary storage device. When an event damaging at least some of the data in the primary storage device occurs, the data is reconstructed using the record stored in the disaster-proof storage unit and at least part of the data stored in the secondary storage device.